'Grimm' star Sasha Roiz: 'The secrets are all coming out'

After what feels like an eternity (it was really just four incredibly long months), NBC's supernatural drama "Grimm" is finally returning with the lucky 13th new episode of its second season. And boy, is it going to be action packed.

Scott Green / NBC /

It's never a good idea to beat up your boss! But Det. Nick (right, played by David Giuntoli) certainly has an understandable reason for giving boss Capt. Renard (Sasha Roiz) a beating.

"In episode 13, the one after the break, it all comes to a head," star Sasha Roiz, who plays Capt. Renard, told The Clicker. "What I like is the secrets are all coming out."

And in particular, his mysterious character's skeletons -- both of the romantic and Wesen-world sort.

"(Nick's) going to discover a lot ... it really is a huge episode," Roiz teased. "Me and Nick face off, and it's going to be fascinating to see where this leads. I think it's going to basically take the trajectory of the show in another direction."

Face off indeed. As the NBC trailer teases, the two law-enforcement hunks come to blows.

"A huge fight!" Giuntoli told us. "And it was ridiculous that when we actually did do that fight, because we're clumsy, we were bears on roller skates! ... We bruised and battered each other's bodies."

The actor told us that both he and Roiz got hurt filming the scene, but it was nothing too serious. "Not beyond bruises. But major, major injuries," Giuntoli said. "I had a bruise like that on my leg. I kneed him in the face!"

"I’m really glad that we had a chance to finally confront each other because I think it’s something the fans had been waiting for a long time," Roiz said during a call with reporters Wednesday. "And we -- as characters and actors -- had been waiting for as well."

When anyone gets into a physical altercation with their boss, things are going to get weird in the office (especially if said boss also gets to know your significant other in a ... umm ... more romantic way). And this will definitely be the case for Det. Nick and his captain.

"It's going to be hard to work with (Renard)!" Giuntoli laughed. "Here's the thing, though. I can't really ... what do I do? I don't quit! I don't tell anybody in the force. So we just kind of have to suck it up and work together, sort of, and hopefully, somehow make amends enough to keep working together."

Renard's not about to let Nick the Wesen-fighting Grimm slip out of his grasp either.

"Ultimately, he needs the Grimm," Roiz said of his character. "That's the most important thing for him right now -- for his protection, for his plans and ambitions -- he desperately needs to be allied with the Grimm. ... It's like having a superhero in your back pocket to protect you!"

Tune in to the return of "Grimm" on March 8 at 9 p.m. on NBC to see if Renard and Nick can put the captain's betrayal behind them after a good fight.